The few explicit items (that the boy has a friend who is, for my money, some sort of baby-griffin-dog-lizard-thing Team Ico has created their own mythos for that players will never hear, that there are guards who impede the boy's progress, that the game is set in decaying ruins surrounded by staggering natural vistas) are surrounded by a number of implications that players can choose to accept or deconstruct, depending on how much free time they have on their hands.